A certain number of indicator apparatuses already exist for adjusting the bearing and/or elevation of reflectors. In particular, U.S. Pat. No. 2,997,914 describes an apparatus suitable for mounting on the fixed glass of a headlight and of occupying a reference position, and then "reading" the beam generated by the headlight to verify that it is suitably oriented relative to the reference. The headlight is fitted with adjustment means that may be conventional or otherwise and these are used to vary the aim of the reflector and of its lamp until satisfactory beam is generated.
A characteristic common to all prior systems lies in the fact that they use light-sensitive means which are placed in the field of the light beam generated by the lamp/reflector pair that is to be adjusted, with the light-sensitive means occupying an accurate reference position. As a function of the light they receive, these light-sensitive means serve to indicate whether or not the beam is properly positioned.
All of such prior art systems are therefore disadvantageous in that they are generally complex and expensive.
The present invention seeks to mitigate these drawbacks of the prior art and to provide an aim-indicating device which is simple and cheap in design and easy to implement.